Propeller mechanism



' April 19, 1949- H. CARSON ET A1. 2,467,964

PROPELLER MECHANISM Filed Jan. 15, 1945 4 Sheets-Sheetl 1 April 19, 1949. NH. CARSON ETAL 2,467,964 PROPELLER MECHANISM l Filed Jan. 15, 1945 4 Sheets-Sheet 2 INVENTR a Howard. Carson BY Mum-i5 T.luer 7 ir/v ATTORNEYS April 19, 1949. H. CARSON ETAL PROPELLER MECHANISM Filed Jan. 15, 1945?` 4 Sheets-Sheet 3 nya INVENTOR TTORN EYJ April 19, 1949. H CARSON Erm.

PROPELLER MEcHANIsM Filed Jan. 15, 1945 4 Sheets-Sheet 4 INVENTOR Howard [.dvm BY Morne. Due? ATTORNEYS Ptented Apr. ,19, 1949 PROPELLER MECHANISM Howard Carson and Morris J. Duer, Dayton, Ohio, assignors to General Motors Corporation, De-

troit, Mich., a corporation of Delaware Application January 15, 1945, semi No. 572,848

Claims.

, This invention relates to controllable pitchl propellers for aircraft and has for an object to simplify the construction of regulators for uid circuits.

One of the particular objects of, the invention is to provide a regulator made up from formed steel members united to form a sealed fluid reservoir.

Another object 'of the invention is to provide a regulator mechanism that will be of little mass, and easily fabricated by production line methods.

Another object of the invention is to provide a regulator mechanism in which the units of fluid circuit control are mountable from the exterior of the reservoir. and in which there is a minimum of outside controls or actuators.

Another object of the invention is to provide a compact valve assembly for fluid circuits, susceptible of speedy replacement, and ,generally housed by a circumferentially disposed and radially extending capsule forming part of the sealed reservoir.

Another object of the invention is to provide a sealed lregulator shell with built-in tubage connections and orifices, and control-unit sockets, withA control units of compact form mounted in the sockets and having definite passages matable with the oricespof the shell.

A still further object of the invention is to provide a fluid circuit control-unit adapted for capsule mounting in a regulator housing, the unit including a pressure control valve, a fluid distributing valve and a pair of control passages with filter devices hydraulically connected between a fluid pressure source port and a pair of control ports.

Other objects and advantages of the present invention will be apparent from the following description, reference being'had to the accornpanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings: .f p

Fig. l is an elevational view with parts in section illustrating an adaptation of the instant in-v vention. f It is a view substantially as indicated y by the line and arrows I-l of Fig. 2.

vtl'xeregulator and breather valve, substantially as indicated by the line and arrows 3-3 vof Fig. 2.

Fig. 4 is a detailed view of the control linkage.

substantially as indicated by the line and arrows 4--4 of Fig. 1.

Fig. 5 is a plan view of the socket adapted to house the control valve assembly, substantially as indicated by the line and arrows 5-5 of Fig. 2.

Fig. 6 `is an elevational view ofthe control valve assembly, substantially as indicated by the arrow 6 of Fig. 7.

- Fig. 7 is a longitudinal sectional view of the same substantially as indicated by the line and arrows l--l of Figs. 6 and 8."

Fig. 8 is a top yplan view of the unit substantially as indicated by the arrow 8 of Fig. 7.

Fig. 9 is a bottom plan view of the kunit substantially as yindicated by the arrow 9 of Fig. 7.

Fig. 10 is a sectional view of the unit through the control ports and associated lter devices substantially as indicated by the line and arrows Ill-I0 of Fig. 8.

Fig. 11 is a sectional view through the unit showing the pressure source port and the pressure control valve substantially as indicated by the line and arrows lI-lll of Fig. 8.

Fig. 12 is a schematic view of the propeller control elements adapted to a iluld circuit for controlling the pitch of the blades.

Referring specifically to the drawings, l0 indicates an engine nosing or gear casingfof an aircraft from which extends in rotatable' relation an engine driven propeller shaft llprovided with splines l4 for driving a propeller hub I6 that provides a plurality of propeller blade sockets I8 journalling blades 20 for pitch 'shift movement. Forshifting the blades in pitch, they are mountedin the sockets by bearings 22 and 24, and enclose torque units 26 in the form of cylinders 28 rigidly coupled to the blades and/enclosing pistons 29 splined thereto atv30 and to axed spindle 32 at 34. The cylinder is thereby divided into a ypair of opposed uid pressure chambers 36 and' 38 each of which is provided with fluid passages leading to a regulator 40 as is now usual in the art and particularly described in the patent to Blanchard et al. 2,307,101. ',Ihus, a tube 42 secured in a clamp bolt`44 extendsfas a guide through the piston 29 to open into the chamber 36, while the innerv end opens into a chamber 46 from which leads a transfer tube 48 anchored in the side ofthe socket I8., to end in an orifice 50. Similar fluid .connections from the chamber 38 may end in an orifice 52 in the side of the socket. The structure is such that fluid pressure directed through the orifice 50 eil'ects radially inward movement of the piston 29 for a decreas- 3 ing pitch shift with a consequential outflow from the chamber 38 through the orlnce 52, while directed application of pressure to the orifice 62 effects an increase pitch shift of the blades.

Directed application of pressure to the torque unit is controlled by the regulator 40 which embraces a fluid reservoir 54, houses a pressure creating means or pump 56, and a compact control valve assembly 58. The regulator is of annular' form and is secured on the hub |6 concentric with the shaft l|2 so that porting blocks 60 and 62 register with the oriiices 50 and 52, of the hub. That is made possible by means of a sleeved extension 64 extending aft of the hub and about which the regulator is centered, and a sleeve nut 'Rabbetted flanges ||4 and ||6 on the outer ends of the nipples operate to seat and orient the units 66 threadedto the hub sleeve at 68 and abutting a ange or part 10 ofthe regulator 40. The regulator housing per se forming the reservoir 54 is made up of concentric drawn or spun steel members 12 and 14, both angular in cross section so that when tted together they form an annular chamber therebetween of L-section including the radial portion `54a and the cylindrical portion 54h thereby rendering the reservoir 54. The member 12 has a cylindrical wall 16 integrally joined to a planar wall 18, and at the inner edge of which is a short ilange 80 of an inside diameter to slide over the sleeve extension 64 of the hub. The member 14 has a. cylindricai wall 82 and planar wall 84 parallelly disposed with respect to like Walls of the member 12, and in addition thereto has a radially outward extending rim 86 joining an outer cylindrical flange 88, as well as an inward cylindrical flange 90, the flanges being dimensioned to closely t within the parts 16 and 80 of the member 12. When so adjusted they are solidly joined in a iluid sealed relation by welding or brazing as indicated at 92.

Before assembly of the members forming the reservoir 54 the members will have been fitted with the elements necessary to provide uid connection with the torque units and with the tubage assembly connecting the control apparatus. That includes the porting blocks 60 and 62 that are located at proper points along the planar wall 18 and that also act as spacers for locatingv the members and limiting the amount of telescoping movement of the members 12 and 14 when they are assembled. Like spacers for concentricity of the parts are provided by the balance anchoring blocks 94 secured in the cylindrical wall of the member 1-2. The tubage assembly includes a pressure supply conduit 96 anchored in a porting block 98 located adjacent a pump station and extending around the side of the member 12 to a porting block |00, while a control passage |02 for the decrease pitch pressure application connects all of the porting blocks 60 in the Wall of the member 12 and leads to a porting block |04. A second control passage |06 connects all of the porting blocks 62 and leads to the same porting block |04 which is located adjacent the station for the control valve assembly as is also the porting block |00. They are so shown in Fig. 5.

At diametrically opposite points of the regulator casing stations are provided for mounting of the pump and control valve assembly. The stations are dened by tubular nipples |08 and ||0 secured in the cylindrical wall 16 of the housing and arranged with their axes on a radius of the axis of propeller rotation. When welded or' brazed imposition as indicated at ||2 they form sockets adjacent the porting blocks for reception 56 and 58 while flanged cap members ||8 and |20 complete the capsule enclosing the units, and are held in fluid tight relation by screw devices |22. Within the capsule formed by the nipple |08 and cap ||8, there is located the pump 66, provision being had by openings |24 through the wall of the nipple and grooves |26 of the pump body for the fluid intake of the pump, the outlet of which opens to the porting block 98 and thence by the piping 96 to the porting block |00 at the station for the control valve assembly. The control valve assembly mounts within its capsule formed by the nipple ||0 and cap |20 in a similar manner since it is inserted within the nipple until "it engages a flange |28 formed on the inner-end of the nipple, or may involve a part of the porting block or blocks at the particular station. Locating means areprovided by which the unit may be seated in but one angular position within the nipple, and in which the fluid ports are properly aligned with the portsto the tube elements connected with the porting blocks. In .the instance of the pumpunit 56, its driving shaft |30 has a splined or like driving engagement with a sleeve shaft |32 journalled in a bushing |34 carried by a nipple |36 secured in the inner wall 14 of the regulator housing.' A pinion |38 secured to the sleeve shaft |32 affords a driving means for the pump and is maintained with a leak-proof joint by a seal ring |40. Actuating means for the control of the valve unit is also mounted on the inner wall of the regulator housing and comprehends anipple |42 within which'is journalled a shaft |44 toV opposite ends of which there are drivingly iixed arms |46 and |48. A seal ring |50 prevents leakage through thev bearing of 4g pressure fluid from the reservoir 54.

The control valve assembly 58 is a compact unit incorporating all of the valving mechanism and movable or active elements entering into the regulation of the iiuid circuit. For detailed description, reference is now made to Figs. 6 to 1l inclusive, where |52,refers to a body ,of cylindrical form fitting within the nipple ||0, and having a plurality of longitudinal-ly extending bores |54, |56, |58, |60 and |62 for housing various of the elements of the control apparatus. Other bores and drillways yboth longitudinally extending and crosswise thereofmake for connecting the control elements as will presently appear from of the body |52, it is provided with a cylindrical recess |64 that will register with the orifice |66 of the porting block |00 to which the :pump supply line 96 is connected. rI he recess |64 in ccoperation with .the orice |66 are designed to enclose' a. resilient rubber-like ring that operates as a fluid seal and yet permits fluid ilow from the pressure line 916 throughthe hole in the ring to a drill passage |68 joining a bore |10, that has a branch |12 opening into the -bore |54 for a pressure control Valve |14, and a branch |16 opening into the bore |56 for 'the distributor valve |18. These, as well as other drill passages, are started on the surf-ace of the block where most convenient to locate the direction, and determine the extent for the proper fluid connections, .and after drilling are in certain instances plugged at their starting ends to establish di. rected ilow of fluid, such 'as indicated generally at |80. Extending from the bore. |66 there are twov other passages leading -each to one of the bores |60 and |62 that house lter units 82 and |84 and terminate in orifices |86, |88 each recessed to receive a exibie seal ring and registerswith oriiices |80 and |82 in the porting block |04 leading to the control passages |02 and |06 respectively. One of these passages includes a bore |84 starting from near the inner end of the bore |56 and extends across the block |52 to join a longitudinal -bore |66 that opens intoa second bore |98 that connects with the top end of the bore |60 for the filter unit |82 in the decrease pitch line. The otherof those passages includes a bore 200 starting from near the out end of increase pressure .port of the bore |56 to extend directly tothe out end of the bore |62 for the ii-lter unl-t |84 'in the increase pitch line. A tap from the increase pitch line is made by bores 202, 204

and 206, 201 between the bore |62 and the bore |54 for the pressure control valve all as will be presently explained. Yet -another b ore 208 ex tends as a spill passage from the bore |54 'to the bore |58 housing the governor spring 2|0. The

. which has a pair of spaced lands 250 and 252 physical structure for 4the connections is shown vin Figs. 6 to 11,'and the schematic and functional arrangement can be followed upon study of Fig. 12.

Reverting to a detailed description of the control elements, the pressure control valveA |14 is shown in Fig. 11, and includes a plunger having a head 2 I2 slidable in and subs-tantially filling the cross-section of the bore |54, there being a notch 2|4 in its edge to form a bleed 'between the two sides thereof. A damping chamber 2|6 .is thereby afforded between the head 2|2 and a plug 2| 8 held in sealed relation within the end of the bore |54 by a keeper pla-te 220 secured to the body |52 by screw devices 222. Aiiixed atV an intermediate -point alongl the stem of the .plunger there is a valve land 224 of small area and arranged to slide within a porting sleeve J22|6 having ports 228 communicating with the spill passage 208. A spring 230 disposed between the portsure from -the pump is always present in the y groove 238 and by means of a port 244 through the porting sleeve is-present in the bore of the sleeve 236. 'I'he sleeve 236 is also ported at 246 for the decrease pitch line, and at -248 for the increase pitch line. The body |52is so arranged that the bores y|56 and |54 are radially extensive of the axis of rotationof the propeller, and the bore of the porting sleeve N286 slidably receives the distributor valve of plunger |18 designed to register with and close 01T the ports 246 and 248 respectively when the valve plunger ing 'sleeve 226 and the head 2|2fof thel valve v normally 'assists centrifugal force to maintain the valve .plunger in the outermost Vposition of its travel, in which the idamping chamber 2| 6 is practically collapsed, and in which the land 224 closes oil? the ports 228 to the spi-l1 passage. When the .propeller is operating, the pump pressure delivered tothe bore |54 through |12 willv be eX- erted on both sides of the head 2|2 and on only one side of the land 22-6, the latterof which opposs the combined force of the centrifugal and spring components thrusting the plungeroutward. Thus as the pressure of the line increases, the spring 230 will be compressed 'and' nally allow the land 224 to uncover the portsl 228, whereupon vthe high pressure in the line land in the bore |54 is relieved through the spill passage. Due to the tap into the increasevr pitchlcontrol passage that is manifest through the passages 204, 206, and 201, additional resistance isoifered.

to the pressurecontrol valve blowing oi at too low a pressure to effect a contemplated change of blade Ipitch. The porting sleeve 226 is provided with a second set of-portsV 232 opening to a chamber 234 behind the land 224 of theplunger; the ports 232 openingv to the bore 201 such that the pressure of the pitch increase line may be applied tothe oppositevside of the land 224 in aiding relation to the spring 230 and the centrifugal force of rotation. By reason of these provisions, when the propeller is decidedly oi speed, or some condition arises in which a quick y and powerful change in blade pitchis needed the,`

pressure regulating device will be temDOr-arily inis in the equilibrium position. The valve plunger |18 has an axial extension 254 slit to receive the notched end 256 of a lever 258 engaging about a cross pin 260 in the slitted end o-f the valve plunger.

' 2|0, the other end of which engages anut 268 carried by a stud 210 extending through the keeper plate 220, there being a flange 212 disposed in the .bore |58 having radial ridges to cooperate with similarly disposed notches in the keeper as at 214 to act as a ratchet or detent prevented .unwanted rotation of the stud. The nut 268 has a radially extending tongue 216 slidably retained within a groove 218 inthe body |52 opening along the bore |58. By reason of those provisions the spring may be adjusted by rotating the stud 210 inland out of the nut 268. The body |52 has a cross channel 280 extending across the inner end thereof to form a housing for the lever and carriage, and the outer end of the cross channel is closed by a plate 282 as particularly shown in Fig. 9 where it is held in position by screw devices 284. 'I'he channel thus acts as a guide for and limits the movement of the carriage 264 which has a depending part 286 traversing a slot 288 in the plate 282 to mark the limits of carriage movement.` Fixed to the carriage 264 there are rollers or wheels'290 that support the carriage within the cross; channel The carriage also supports a roller stop 282 that may be engaged by the lever when at the extreme of decrease Apitch shift. Movement of the carriage is effected by means of the double lever |46 and I| 48 pivotally supported'in the inner wall of the regulator housing as earlier described. In assembling the control valve assembly with the `regulator housingthe dependingy part 286 is registeredwith a slot 284 in the leverv |46 'so thatoscillation of the lever |48 will eiect the movement of the carriage along the lgovernor lever 258. The lever |46 carries apair of spacers or rubbing blocksk 286 to assure that the lever will not be depressed into engagement with the The opposite end of the lever is sup- L ported on a movable fulcr'um in the form of a regulator housing wall 82, when the unit is assembled within its socket. The porting blocks |08 and |04 are suitably recessed at 298 to receive with clearance the screw devices 284 so that a perfect fluid seal may be perfected between the body |52 and the porting blocks.

The governing valve in performing its function directs iluid pressure to one or the .other of the ports 240 or 242 from the pressure port 2,44. If the directed pressure is through the port 240it is applied through the bores |94, |96 and |98 to the bore |60 for the filter |82 of the decrease pitch pressure line. pressure is through the port 242 it is applied through the bore 200 to the bore |62 for the lter |84 in the increase pitch pressure line. Both of the filter units are identical such that a description of one will suiilce for both. A spool member 300 is provided that closely fits the bores |60 and |62 and `is long enough to extend the length thereof substantially as shown .in Fig. 10. An end bore 302 of the spool leaves a closed end 304 with outside castellations 306 adapted to engage the end of the bores |60 and |62. A peripheral narrowy groove. 308 Yis so located as to registerwith the ends of the bores connecting with the distributor valve, and ports 3|0 through the spool connect. the groove 308 with the bore 302. A considerable length of the spool is reduced to make a lodgement for a filtering screen 3|2, and a plurality of holes 3|3 account for nuid ilow from the bore 302 to and through the screen. To prevent against leakage seal rings 3|4 are adopted and the lter units are retained within the bores by the keeper plate 220 heretofore mentioned.

When the units, that is, the pump unit 56 and the controller valve unit 58, are secured within their respective sockets and the covers are secured in place by the screw devices |22, the regulator housing forms a completely sealed unit, since there is afforded fluid seals at 3|6 between the covers and the unit nipples, at |40, for the pump shaft, and at |50, for the journal of the carriage shifting lever. A filler and drain opening is provided for the reservoir by a nipple 3|8 and screw plug 320. `An access opening in the cap |20 for the control valve may be closed by a screw plug 322. That construction would normally leave the reservoir 54 without the possibility of pressure change to follow exterior pressure changes, since the reservoir is otherwise integrally bonded at its seams and junctures to prevent fluid leakage. A breather valve assembly 324 is therefore mounted in the cylindrical wall 16 of the outer housing member substantially as shown in Fig. 3, where a nipple 326 is radially disposed to threadedly receive a body member 328. The head 328 has a tubular extension 330 ending in an orince 332 adjacent the inner ange 80 of the housing member. Housed within the extension 330 there is a needle member 334 urged by a spring 336 to close the orifice 332. The bore of the tubular extension 330 is closed by a plug 338 grooved at 340 to open into a cross passage 342 in the head 328. The plug 338 also forms a seat for the out end of the spring. and the breather unit when threaded into place extends into the branch 54a of the reservoir with the needle 334 disposed with its length radially of the axis of propeller rotation. When the propeller is rotating the reservoir is also rotating and the uid content within the reservoir will be thrown by centrifugal force against the cylindrical wail 16 of the reservoir. Since it is If the directedv customary to nll the reservoir only about half full with operating fluid, there will be no fluid in the region of the oriilce 332 ofthe breather valve while the propelle is rotating. Due to the design Iand location of the breather valve, the needle 334 responds to centrifugal force at a predetermined speed to open the orifice 332, aftez` which any differential of pressure between the inside and outside of the reservoir may be equalized by flow through the valve unit. Since the operating fluid is disposed along the cylindrical wall 16 away from the orifice of the valve unit the only now through the valve unit will be of a gaseous content and not the operating uid.

Actuator mechanism for the pump 56 and controller units 58 are provided `as detailed in Figs. 1 to 4 inclusive, and incorporate an adapter assembly 350 concentric with the regulator and disposed between the regulator and the engine nosing. Secured within the flange 88 of the regulator housing member 14 there is a seating ring 352 adapted to seat the outer race 354 of a ball or other anti-friction bearing 356, which is held in place by a flange ring 358 and screw devices 360. A guard member 362 extends across the gap of the bearing to engage the inner race member 364 mountedon the outside of a pumpdriving gear 306. A spacer and guide `ring 368 abuts the pump driving gear and provides a channel for reception of an adjusting ring 310 disposed between the guide ring 366 and a flange 312 of an adapter sleeve 314 which surrounds the sleeve nut 66 and extends the length of the regulator to telescopcally engage within a lubrication seal 316 mounted on the planar wall 84 of the housing member 14, Screw devices 318 secure a clip.

380 to the assembly and pass through the spacer 368 to thread into the p ump driving gear 366 so as to secure those elements in rigid relation. Extending from the clip 380 thereis an arm 382 adapted to engage a notch in a block 384 secured adjacent a piloting plate 386 mounted on the casing |0. Rotation of the propeller thus causes the regulator to rotate relative to the adapter assembly since the latter has a rotative bearing within the same lby means of the antifriction means 358, and is restrained against rotating with the propeller by the arm and notch linkage 382,384. An arm 388 suitable for linkage to the cockpit of the craft is attached to the adjusting ring 310 as shown in Fig. l, and plays along anotch in the guide ring 388 to oscillate the adjusting ring which has axially extending tongues 390 engaging within notches 392 of a sleeve 334 slidably mounted on the adapter sleeve 314, The sleeve also has a cam slot therein as shown at -396 that engages overa roller or pin 398 secured in the adapter sleeve 314, such that oscillation of the sleeveY 394by the adjusting ring 310 will eiectnmovement of that sleeve axially of the adapter sleeve 314. Carried by the sleeve 394 there is a control ring 400 adapted to be traversed'by a shoe 402 mounted onthe end of the arm |48 for the governor carriage adjusting mechanism.

Any question of operation should now be clearly discernible by reference to Fig. 12 where the elements of the control system are shown in their functional relation and practically devoid of specific structure. It should be obvious that operating fluid picked up by the pump 58 is delivered to the distributor valve through the line |16, the

pressure being limited by the valve 58 which controls the pressure in the line |16 to satisfy the demands of the devices to be operated by the governor valve. The operating the governor valve goes to-either the decrease pitch line |02 through the port 240 andthe filter |82, or to the increase pitch line |06through the port 242 and the filter |84.- When the pressure is directed to the increase pitch line, and because that application meets with the natural tendency of the blade to shift to a decrease pitch position, there is a feed-back connection from the increase pitch port 242 to the pressure control valve 58 which tends to raise the blow-off limit and maintain a pressure potential suitable for the increased demand. The directed pressure by the governor valve thus reaches either the chamber 36 to force the piston 29 in a, pitch decreasing direction, or the chamber 38 to force the piston in the opposite direction. Obviously, movement of the piston in one direction is made possible by the governor valve opening a relief to the other side throughthe other one of the control passages and filters. Thus when pressure is applied to the ports 240, venting of the torque unit is effected through the port 242 to the interior of the porting sleeve 236 and out through the openings 404 and 406 in the keeper plate 220 to the bore |58 for the governor spring, and thence to the reservoir 54. Movement of the arm388 operates to select the speed level at which the governor mechanism will effect constant speed control of the propeller. Moving the fulcrum l20'! along the lever 258 changes the relation of the moment arms through which the centrifugal force and the force of spring 2|0 act upon the valve and lever. The force of the spring remains substantially constant as determined on the ground by the stud 210, and always acts through the same moment arm except upon shift of the-fulcrum to the feathering position, which is substantially that shown by the dotted lines in Fig. 12. The shift -of the fulcrum can .be accomplished while the propeller is rotating and' when effected to the dotted line position so changes the force valiies acting on the valve and lever that the centrifugal and spring forces are now in aiding relation tending to move the valve plunger |78 against the increase pitch stop embodied in the keeper plate 220. 'I'he operating fluid will thence be directed to the chamber 38 regardless of the speed of propeller rotation, and will effect movement of the blades 20 to the edge on position.

Due to the fact that the pump and control unit are mounted in capsules that can be readily opened without disassembling the regulator, they can be easily and quickly repaired, cleaned, or replaced without suppressing the operation of the craft for hours or'days as might otherwise be the case.

While the embodiment of the present invention nuid distributed bri` as herein disclosed, constitutes a preferred form,

it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

l. In a fluid pressure regulator for an aircraft propeller, the combination comprising, a pair of formed sheet metal rings telesccpically engageable to provide an annular enclosure, means bonding the engaging portions of the rings to seal the enclosure into a fluid tight reservoir, radially extending sockets locatedK in the outer wall of the enclosure, fluid pressure developing andl control units located in the sockets, means connecting the units into a, uid circuit and caps covering the units and secured to the sockets in sealing relation.

2. In a fiuid pressure regulator for an aircraft propeller, the combination comprising, a pair of formed sheet metal rings telesccpically engaged to provide a pair of concentric spaced walls of a reservoir,` means for sealing the engaging portions of the rings to render the reservoir tight against .fluid leakage, socketed openings in the outer of the concentric walls, fluid pressure de-y veloping and control units disposed in the sockets with cap members enclosing the units for perfecting their inclusion within the sealed reservoir, means hydraulically connecting the units with the reservoir, and operating and adjusting means for the units extending through the inner one of the spaced concentric walls.

3. In 'a fluid pressure regulator for an aircraft propeller, the combination comprising, a formed sheet metal ring having a pair of cylindrical concentrically spaced walls, a second formed sheet metal ring having cylindrical flanges adapted to engage each a flange of said first ring, a tubage assembly secured to a wall of the rst mentioned ring and connected with a motive device to`be operated, sockets opening through the outer one of the ring walls, fluid pressure developing and control units secured in the sockets and adapted to register with porting blocks provided by the tubage assembly, operating means carried by the inner ring for coupling with the units, and means for sealing the engaging portions of the rings to render a fluid tight reservoir enclosing the flui pressure developing and control units.

4. In s, fluid pressure regulator for an aircraft, the combination comprising, an annular reservoir arranged concentric with an axis of rotation, for receiving a charge of operating fluid, radially extending tubular sockets circumferentially spaced about and opening into the reservoir, a fiuid actuating unit mounted in one of the sockets and a fluid control unit mounted in an oppositely disposed socket, means for sealing o the sockets to enclose the units in exposed relation to the reservoir, a tubage assembly within the reservoir having porting blocksretained in registry with the units, and means extending through a wall of the reservoir for actuating both units.

5. The combination set' forth in claim 4 wherein mounting of the units in the sockets and sealing off the sockets makes fluid circuit connections between' the respective units.

6. The combination set forth in claim 4 wherein the fluid control unit comprises a compact assembly of a pressure regulating valve, a governor valve and fiuid filter units hydraulically con nected to fluid circuit ports.

7.' The combination set forth in claim 4 wherein the fiuid'control unit comprises a^body with longla tudinal and cross bores housing and hydraulically connecting a pressurecontrol valve, a fluid pressure directing valve and control passages with filters, and ending with fiuid circuit ports.

8. The combination set forth in claim .4 wherein the uid control unit comprises a body wlthlongitudinal and cross bores housing and hydraulically connecting a pressure control valve, a fluid pressure directing valve and control passages with filters, and ending with fluid circuitv ports, one of said control passages having a feed-back to the 10. In a fluid circuit controller, a control valve assembly adapted for removable mounting in a peripheral wall of a regulator a capsule, mounted within the regulator and opening to the exterior thereof, sai'd assembly comprising in combination, a cylindrical body disposed in the capsule and having longitudinal bores for chambering elements of a'iluid controller apparatus, and cross bores for connecting the elements into the fluid circuit, a

pressure control valve located in one of the longitudinal bores for limiting the line pressure to a normal value, a speed responsive governingvalve located in one of the other longitudinal bores for directing lthe limited pressure to either of two other longitudinal bores, filter units in each of said two other bores, and a fluid connection between one of said two other bores and said pressure control valve for temporarily raising the limit of said line pressure above the normal pressure in accordance with the demands of said one bore when pressure is directed to it and a removable cap secured to the regulator over the opening for enclosingA the control valve assembly.

11.' Regulator apparatus for controlling pitch of propeller blades, said regulator comprising an annular sealed reservoir, a fluid pressure source,y

a fluid line in the reservoir for the pressure source, and means for controlling the fluid pressure cornprislng a valve body interposed inthe fluid line,

said body providing interconnected passages and extending bores for housing said valves, with transverse bores for connecting the axial bores one with another and with the pressure source.

13. The combination set forth in claim l1 wherein the said body comprises a cylindrical block adapted to seat within a capsule for making connection with the iluid line, and has a plurality of axially extending bores for housing a pressure control valve, a distributing valve, and a pair of filter units, there being cross bores for appropriately connecting the pressure control valve with the distributing valve and for connecting all of the valves into the fluid pressure source.

14. The combination set forth in claim .11 wherein the said body comprises a cylindrical block adapted to seat within a capsule for making connection with the fluid line, and has axially extending bores for housing the valves including a pressure control valve, a distributing valve with control ports, and a feed-backfrom one of the control ports leading to the pressure control valve. Y'

15. The combination set forth in claim 11 wherein the passages provided by the body include a pressure control passage housing a pressure control valve, a pressure distributing passage with control ports housing a distributing valve, a cross connection between one of the control ports and the pressure control passage, and filter passages housing iilter units and connected with the control ports.

HOWARD CARSON. MORRIS J. DUER.

REFERENCES CITED .The Vfollowing references are of record in the file of this patent:

UNITED STATES' PATENTS Number Name Date Re. 4,492 Brundred Aug.\1, 1871 1,829,655 Huguenin Oct. 27, 1931 2,900,246 I Neely May 7, 1935 2,307,102 Blanchard et al Jan. 5, 1943 

